In anthracite and bituminous coal mining, a person who: (1) uses hand
tools to extract coal in underground workings; (2) cuts out a channel
under the bottom of the working face of coal (undercutting) with a pick,
working several feet back into the seam; (3) breaks down a coalface with a
pick; (4) bores holes with an augerlike drill for blasting, and inserts
and sets off explosives in holes to break down coal; (5) shovels coal into
cars and pushes them to a haulageway. Also called hand cutter; hand miner;
hand pick miner; pick-and-shovel miner. DOT
An earlier practice whereby miners paid a blacksmith for sharpening their
picks. Nelson
A small haulage engine used for pulling light loads over short distances;
used at junctions, loading points, and haulage transfer points.
See also:winch; spotting hoist. Nelson
Tongs for handling hot metal. Webster 3rd
a. Syn. for lift, as applied to hoisting drill rods from a borehole.
Long
b. An angular crosscut, through which coal is hauled from one entry to
another. See also:shoo-fly
c. See:geophone; detector.
d. Transfer of metal from tools to a part, or from a part to tools, during
a forming operation. ASM, 1
e. In Alaska, a gold nugget picked up during mining operations prior to
sluicing.
A laboratory procedure used in investigating the floatability of minerals.
A few grains, sized between 60 and 120 mesh, are placed, after suitable
surface cleansing, under water in an observation cell which is controlled
for pH, reagent concentration, temperature, and conditioning time. An air
bubble is pressed down on the particles and then raised; the degree and
tenacity with which they cling to it are observed. Pryor, 3
Cutting coal with a pick, as in driving headings. Fay
A steel bar, usually of 7/8-in (2.22-cm) stock and about 4 ft (1.2 m)
long, with each end sharpened, bent out at an angle of 45 degrees , the
bends being 3 to 6 in (7.6 to 15.2 cm) from each end. Hess
A former name for chromian spinel, (Mg,Fe)(Al,Cr)2 O4 .
An etching reagent consisting of a 2% to 5% solution of picric acid in
ethyl alcohol. It may be used for plain carbon and low-alloy steels.
Osborne
A yellow crystalline compound, C6 H3 N3 O7 ,
obtained variously, such as by the action of nitric acid on phenol. It is
used in dyeing and is an ingredient in certain explosives. Also called
carbazotic acid; chrysolepic acid; trinitrophenic acid.
Standard, 2
Olivine-rich basalt, as formed by the settling of olivine in thick flows
and sills. Commonly contains 50% or more olivine. AGI
Magnesium chromite, MgCr2 O4 ; melting point, 2,250 degrees
C; sp gr, 4.41. This spinel can be synthesized by heating a mixture of the
two oxides at 1,600 degrees C; it is formed (usually with other spinels in
solid solution) in fired chrome-magnesite refractories. Picrochromite is
highly refractory but when heated at 2,000 degrees C, the Cr2 O
3 slowly volatilizes. See also:magnesiochromite
An asbestiform antigorite serpentine.
a. A monoclinic mineral, K2 Mg(SO4 )2 .6H2 O ;
forms highly soluble masses or crusts around fumaroles; also a rare,
advanced desiccation constituent of marine evaporites. Formerly called
schoenite.
b. A mineral group including boussingaultite, cyanochroite, mohrite,
nickel-boussingaultite, and picromerite.
A screen to shelter workers from falling water. Zern
A process for the production of magnesium by the reduction of magnesium
oxide with ferrosilicon. ASM, 1
A local term for an intermediate pack without supporting walls.
TIME
A process by which magma eats into its roof by engulfing relatively small
isolated blocks, which presumably sink to depth where they are
assimilated. See also:magmatic stoping
The performance of underground work on the basis of an agreement between a
miner and the mine manager. Payment may be made by the yard of advance of
a heading or tunnel or per ton or cubic yard of coal or ore removed. In
ripping work, payment may be made by the yard advance of excavation to a
specified width and height; strip packing may be built at a certain sum
per yard advance or cubic yard of filling. See also:contract work;
yardage. Nelson